The present disclosure describes using the JTAG Tap's TMS and/or TCK terminals as general purpose serial Input/Output (I/O) Manchester coded communication terminals. The Tap's TMS and/or TCK terminal can be used as a serial I/O communication channel between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC. The use of the TMS and/or TCK terminal as serial I/O channels, as described, does not effect the standardized operation of the JTAG Tap, since the TMS and/or TCK I/O operations occur while the Tap is placed in a non-active steady state.

Provided are scan device and method of diagnosing scan chain fault. The scan device for diagnosing a fault includes a scan partition including a plurality of scan chains which include path control scan flipflops connected to scan flipflops in cascade. In the scan partition, connection paths of the scan flipflops are controllable. The connection paths of the path control scan flipflops are controlled to detect a position of a fault such that a fault range in the scan partition is reduced to diagnose the fault.

A method, system, and/or computer program product of scanning of an integrated circuit including chiplets to isolate fault locations is provided herein. The scanning of the integrated circuit includes providing, by a pervasive of the integrated circuit, an input to the chiplets. Each of the chiplets can include a pervasive satellite, a multiplexer, and latches. The scanning of the integrated circuit includes also scanning, by each pervasive satellite of the chiplets, data based on the input via the multiplexer into the latches to produce scan data for each of the chiplets. The scanning of the integrated circuit also includes comparing, by the pervasive of the integrated circuit, the scan data of each of the chiplets to expectant data stored on the pervasive to isolate the fault locations.

A Joint Test Access Group (JTAG) device can include a Joint Test Access Group (JTAG) port, transport layer circuitry to provide a communication to and from a debug device, and packet interpreter circuitry communicatively coupled between the JTAG port and the transport layer circuitry, the packet interpreter circuitry to translate data in a packet from the debug device into a sequence of bits to be provided to the JTAG port.

Provided are scan device and method of diagnosing scan chain fault. The scan device for diagnosing a fault includes a scan partition including a plurality of scan chains which include path control scan flipflops connected to scan flipflops in cascade. In the scan partition, connection paths of the scan flipflops are controllable. The connection paths of the path control scan flipflops are controlled to detect a position of a fault such that a fault range in the scan partition is reduced to diagnose the fault.

A test coverage rate improvement system for pins of tested circuit board and a method thereof are disclosed. In the system, partial pins of a circuit board connector in a tested circuit board are not electrically connected to the boundary scan chip, test pins of the test pin board are pressed with the partial pins by a fixture of a boundary scan interconnect testing workstation to electrically connect the test pins to the partial pins. A test access port controller receives a detection signal for detecting the partial pins, which are not electrically connected to the boundary scan chip, of the circuit board connector through the test pin board from the test adapter card, and determines whether conduction is formed based on the detection signal, thereby achieving the technical effect of improving a test coverage rate for the pins of the tested circuit board.

The present disclosure describes using the JTAG Tap's TMS and/or TCK terminals as general purpose serial Input/Output (I/O) Manchester coded communication terminals. The Tap's TMS and/or TCK terminal can be used as a serial I/O communication channel between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC. The use of the TMS and/or TCK terminal as serial I/O channels, as described, does not effect the standardized operation of the JTAG Tap, since the TMS and/or TCK I/O operations occur while the Tap is placed in a non-active steady state.

The present disclosure describes using the JTAG Tap's TMS and/or TCK terminals as general purpose serial Input/Output (I/O) Manchester coded communication terminals. The Tap's TMS and/or TCK terminal can be used as a serial I/O communication channel between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC. The use of the TMS and/or TCK terminal as serial I/O channels, as described, does not effect the standardized operation of the JTAG Tap, since the TMS and/or TCK I/O operations occur while the Tap is placed in a non-active steady state.

A proposed linear time compactor (LTC) with a means of significantly reducing the X-masking effect for designs with X's and supports high levels of test data compression where: 1) The LTC consists of two parts that are unloaded into a tester through an output serializer. 2) The first part is unloaded per t shift cycles while the second part is unloaded once per test pattern. 3) One part of the LTC divides scan chains into groups such that X-masking effect between groups of scan chains is impossible. 4) One part of LTC divides shift cycles into groups such that X-masking effect between groups of shift cycles is impossible.
Consequently, the X-masking effect in the proposed LTC is significantly reduced.

Exemplary embodiments of the present disclosure relate to a clock distribution network for a scan design, which may include, for example, a clock signal network(s), and a plurality of partitioned clock signal networks coupled to the clock signal network(s) through a controlling logic(s); where the controlling logic(s) may be configured to stagger a clock signal from the clock signal network(s), and where each of the partitioned clock signal networks may be connected to a group of flip-flops. A first partitioned clock signal network of the partitioned clock signal networks may be connected to a first group of flip-flops and a second partitioned clock signal network of the partitioned clock signal networks may be connected to a second group of flip-flops, and where the first group of flip-flops may be different than the second group of flip-flops. The controlling logic(s) may include a shift register(s).